This invention relates to a call control system for use in a SCP (Service Control Point) included in an intelligent network (which will often be abbreviated to an IN).
Nowadays, consideration has been directed toward making a network highly intelligent in order to respond to a wide variety of requirements for communications. Such consideration might become more important in connection with an advanced communication network as well as a broadband network and a personalized network. Heretofore, an IN (Intelligent Network) has been proposed so as to make a network highly intelligent.
In such an IN, a plurality of intelligent peripherals (will be abbreviated to IP) and a plurality of vender feature nodes (VFN) are used as terminal devices. Each of the terminal devices is connected to a service control point (will be abbreviated to SCP) through a service switching point (will be simply called SSP) which is operable in a manner similar to a conventional exchange. Each of the SCPs is managed by a service management system (SMS) which has a database.
In a conventional IN, high intelligence is not given to each SSP but is concentrated into each SCP to which the SSP is connected by transmitting a service control request message from the SSP to the SCP. The SCP executes a call control operation in accordance with a service control request message to provide service to a user connected through the SSP to each terminal device. The call control operation is peculiar to or determined by the service control request message.
From this fact, it is understood in the conventional IN that the SCP should be designed to respond to the service control request message and can provide the service to each user as long as the service control request message has the format determined for the SCP.
Herein, the SSP may not always be connected to the terminal devices which have the service control request message of the same format but may be connected to a plurality of the terminal devices which are different in species from one another. In this case, the SCP is supplied from each of the terminal devices through the SSP with a service control request message of a format which is different from one another to specify the species of the terminal devices.
In addition, a new model of the SSP may be partially substituted into the IN for an old model of the SSP and may be connected to the SCP in common with the old model SSP. This results in coexistence of the old and the new model SSPs in the conventional IN.
Under these circumstances, each SCP in the conventional IN can neither respond to the different service control request messages nor can cope with the coexistence of the old and the new model SSPs.
It is an object of this invention to provide an intelligent network (IN) which can conveniently respond to a plurality of service control request messages which are different from each other.
It is another object of this invention to provide an intelligent network (IN) of the type described, which can allow both old and new model SSPs to be connected to a common SCP.
It is yet another object of this invention to provide an SCP which is applicable to an IN of the type described.
It is still another object of this invention to provide a method of controlling a plurality of service control request messages in a single SCP used in the IN.
An SCP call control system according to the invention comprises at least one SCP and a plurality of SSPs which are configured to send service control request messages each including a source address. The SCP comprises a call model determining unit which extracts a source address from the received call control request message and which determines a call model corresponding to the source address, a call model switching unit which switches to a resource address of the determined call model, a resource managing unit which manages a resource of a currently used call model, and a resource accessing unit which allows a service logic program actually providing a service to access the switched resource.
According to the invention, plural kinds of service control request messages can be treated in a single SCP.